Answer:
The measurement of the third angle would be 139 degrees.
Step-by-step explanation:
Using the triangle sum theorem, you already know that all interior angles of a triangle add up to 180 degrees. So since you already have two angle measurements, all you have to do is add them together and subtract them from 180 degrees. In this case it is 29+12, which equals 41. Now you subtract that from 180 and get 139.
I hope this helps!
